SkyOS

SkyOS is yet another new OS for x86 PCs. Its design is pretty standard; monolithic kernel and growing with a mushroom- like development, features and code being added as needed without much planning. However, it boasts impressive functionality (IMHO) for a project written from scratch: not only it runs programs, features a GUI and all common drivers for pc hardware, but as well a TCP/IP stack and other goodies. Even if there isn't much thought put into design, the amount of work done deserves respect. A nice project to join if you want to work with a large base of already working code and a functional system.